It is often necessary to remove the cap on a pipe wherein the cap is close fit to the pipe and difficult to access. Often the cap will be "frozen" to the pipe, for example, with steel pipes which have become rust bound, or with plastic pipes, such as formed of polyvinyl chloride (PVC) plastic, wherein the cap has been push fit onto the pipe, so close as to be virtually impossible to remove without some form of hammering action. Such pipes are often deeply buried in holes or shafts making it extremely difficult to get to a vantage point beneath the cap so that a hammering action can be delivered to the underside of the cap to dislodge it. Lifting jacks of various sorts have been devised, for example, in which tongues are provided with grappling hooks and hoisted over an area to be lifted by a standard. These devices have pre-set dimensions and often involve tedious steps in set-up and use. See, for example, Weber U.S. Pat. No. 268,328 and Parks U.S. Pat. No. 802,588. A number of devices have suggested the use of curved grabbers for specialized purposes such as in lamp removal or to pull battery terminals or spark plugs. See, for example, Russian U.S. Pat. No. 430,525; Kratky U.S. Pat. No. 1,996,967; and Clark U.S. Pat. No. 4,125,938. Various hammering mechanisms have been proposed to remove valve caps, nails and staples, axles and engine components, or the like, such as in Seppmann U.S. Pat. No. 1,525,894; Brouhard et al U.S. Pat. No. 1,381,890; Blume et al U.S. Pat. No. 1,627,477; Colerick U.S. Pat. No. 1,747,053; Gadberry U.S. Pat. No. 3,739,452; and Smith U.S. Pat. No. 3,280,455. A variety of other mechanisms have been proposed for engaging the bight portion of a pulley, cap or the like, to pull or otherwise draw the object away from its seat. See, for example, Cooney U.S. Pat. No. 1,877,011; Johnson U.S. Pat. No. 2,851,769; Swedish U.S. Pat. No. 189,617; Johnson et al U.S. Pat. No. 1,893,414; Sturm U.S. Pat. No. 2,519,204; Knudsen U.S. Pat. No. 2,561,577; Carlson et at U.S. Pat. No. 3,177,571; and Lunycz U.S. Pat. No. 4,122,599.
None of these devices are useful to accomplish the desired purpose of removing strongly held objects such as a "frozen" cap from a pipe. Those devices using a jack and standard require a surface that must be capable of supporting the standard without dig-in and these devices generally lack the flexibility necessary for many on-site uses. Those devices which employ a hammering operation do so in a manner wherein the hammering component is held by the hand and quickly slid smartly, upwardly against a retainer such as a nut or alike. These devices inherently impart a limited amount of hammering force.
The present invention overcomes the deficiencies of the art and provides a dislodgement device which can not only be used to readily and rapidly dislodge a frozen cap from a pipe, but includes principles of operation that are adaptable to a number of other situations where dislodgement of a problem object is desired. In the present invention, a device is provided for dislodging an object, for example a cap that is close fit over the top of an upright pipe, in which a handle and a grip are interconnected by means of slide bars and a shank with a weight member and an impact member. The handle and grip are each formed to be held by a user. The impact member can be a pair of tongs. The slide bars are fixed to the weight member, disposed through one end of the grip and connected to the handle. The shank is slidably disposed through the weight, and is fixed to the grip on one side of the weight and to the tongs on the other side of the weight. The tongs include a plurality of pivotally connected links and are formed with elongate arms terminating distally with jaws formed to impact against a horizontally disposed surface of the cap. The tongs tend to close when freely suspended from the shank enabling it to slip over the cap to contact it from below the cap. Lifting of the handle impacts the weight against the grip to transmit a hammering force to the jaws, dislodging the cap.
More particularly, a dislodgement device is provided that includes a handle formed to be held by one hand of a user and a grip below the handle formed at one end so as to be held by the other hand of a user. The grip defines a pair of openings at its other end through which a pair of slide bars extend and which are fixed to the handle. The lower ends of the slide bars are fixed to a weight member so that the handle can draw the weighted member up against the underside of the grip. The weighted member is centrally formed with an opening to accommodate a shank which is fixed to the underside of the grip and on its opposite end to a yoke which serves as a fulcrum for a pair of tongs.
The tongs are formed distally with jaws that are curved to fit around a pipe structure so that the upper edges of the jaws can impact against the bottom edge of the cap. The tongs include a plurality of pivotally connected links and are formed with distal elongate arms terminating at the jaws. This structure causes the tongs to tend to close when freely suspended from the yoke, enabling a worker to simply slip the tongs over the cap on a pipe, the jaws sliding along the surface of the cap until it reaches the pipe and then rests against the surface of the pipe. By pulling upwardly on the grip, the worker then secures the impact surface of the jaws against the horizontally disposed underside surface of the cap. At that point, with the worker's other hand on the handle, he simply has to quickly raise that handle to smartly draw the weight, as a hammer, against the grip, which serves, at that point, as an anvil for the hammer. This results in transmitting of a hammering force to the jaws of the tongs with consequent shock dislodgement of the cap from the pipe.